This application claims priority under 35 U.S.C. xc2xa7xc2xa7119 and/or 365 to 9824300.9 filed in United Kingdom on Nov. 5, 1998; the entire content of which is hereby incorporated by reference.
The invention relates to the sending of a dialled telephone number, and in particular, to eliminating the need to press a xe2x80x9cSENDxe2x80x9d button after dialling a telephone number intended for a mobile network, for example when dialling on a fixed line telephone connected to a Fixed Access Unit.
A Fixed Access Unit (FAU) is an unit that enables conventional fixed line subscriber equipment, for example conventional wired telephones and facsimile machines, to be connected to a mobile telephone network. The FAU acts as the interface between the mobile environment and the fixed environment.
The role of the FAU is to convert mobile network signals and protocols into signals and protocols recognised by the fixed network, and vice versa.
When making a telephone call from a mobile telephone, a caller has to press a xe2x80x9cSENDxe2x80x9d key after the dialled digits have been entered. The purpose of the xe2x80x9cSENDxe2x80x9d signal is to allow the dialling operation to be carried out before connecting to a radio channel, thereby reducing the time which the caller is connected to the radio channel. This is turn reduces both the cost of a call and the traffic on the mobile network.
This requirement of having to press a xe2x80x9cSENDxe2x80x9d button poses a problem when dialling from a fixed line telephone which is connected to a FAU.
Some prior art systems overcome this problem by requiring the user to press some other key on the conventional telephone, for example the xe2x80x9c*xe2x80x9d or xe2x80x9c#xe2x80x9d keys, to send the dialled telephone number. This has the disadvantage that it does not allow the user to make any USSD (Unstructured Supplementary Services Data) or public MMI (Man Machine Interface) calls, whereby the xe2x80x9c*xe2x80x9d and/or xe2x80x9c#xe2x80x9d keys have other meanings.
FIG. 1 shows the dialling procedure according to another prior art system. After receiving each dialled digit in step S1, a counter is incremented in step S2. The system then checks in step S3 whether the counter has reached a preset value corresponding to the expected number of digits making up the telephone number. If not, it returns to step S1 and waits for the next dialled digit to be entered. If the counter has reached the preset value in step S3, it assumes that the complete telephone number has been entered, and appends the xe2x80x9cSENDxe2x80x9d signal to the dialled digits in step S4. In other words, the system automatically appends a xe2x80x9cSENDxe2x80x9d signal after a predetermined number of digits have been dialled.
This type of system suffers from the disadvantage that it relies on a standard number of digits making up a telephone number. However, this is not always possible, for example, when making a combination of local, national and international calls.
FIG. 2 shows the dialling procedure according to another prior art system. After the first dialled digit is received in step S10, a timer is started in step S11. In step S12, the system determines whether another digit has been entered before the timer has timed-out. If a digit has been entered within this time, the timer is reset and restarted in step S11, and the system again determines whether another digit has been entered before the timer has timed-out. If no digits are entered during this time, the system assumes that the caller has completed the dialling process, and appends the xe2x80x9cSENDxe2x80x9d signal in step S13 to the dialled digits that have already been received. In other words, if a predetermined period of time has lapsed without a key being pressed, it is assumed that the caller has finished dialling. This type of system suffers from the disadvantage of increasing the call set-up time.
The aim of the present invention is to overcome the disadvantages mentioned above, by having a dialling apparatus that does not require the pressing of a xe2x80x9cSENDxe2x80x9d key, does not rely on a predetermined number of digits in the telephone number, and does not delay the sending of the dialled telephone number.
According to the invention, there is provided a dialling apparatus comprising;
means for determining from first and second dialled digits how many digits constitute a telephone number to be subsequently dialled;
means for determining when the digits constituting the telephone number have been dialled; and,
means for automatically appending an end-of-dialling signal to the end of the telephone number.